Each Sunday, our staff of college football experts will offer thoughts on things they learned over the weekend.

Olin Buchanan

Stanford can run it, too. Andrew Luck doesn't need to pass for 300 yards for the Cardinal to post a big victory. Luck threw for 169 yards and two touchdowns, but the Cardinal's running game more than compensated for Luck's modest passing output. Stepfan Taylor rushed for 138 yards, Tyler Gaffney for 117 and Anthony Wilkerson 93 as Stanford rolled up 446 rushing yards in a 65-21 romp over Washington.

Concerns about Oklahoma's defense are justified. Although Oklahoma was ranked No. 1 to start the season, there were some questions about the Sooners' defense. Those doubts proved legitimate. The Sooners gave up 572 yards of total offense and Seth Doege threw four touchdown passes as Texas Tech upset OU 41-38 to deal the Sooners only their third loss in Norman in the Bob Stoops era. More important, the loss may have ended OU's national championship hopes.

Mike Huguenin

Wisconsin finds defense matters. Wisconsin's offense is a good one, with QB Russell Wilson, two good tailbacks, a big line and solid receivers. But there were questions about the Badgers' defense, questions that hadn't been answered this season because that unit hadn't been tested. Well, it had a test Saturday, and its failing grade means the Badgers are an extreme long shot to play for the national title. Michigan State's offense hadn't done much of anything against good defenses this season. The Spartans' only games with more than 400 yards came against Central Michigan and Florida Atlantic. They didn't get 400 against Wisconsin, either -- but they got 399 and the last 44 cost the Badgers big-time.

USC has some pride. The Trojans are ineligible for the Pac-12 title and for the postseason, but they wrecked host Notre Dame's BCS hopes with a 31-17 victory. Next weekend, they will try to wreck Stanford's national title hopes. Coach Lane Kiffin mentioned last week that despite being 5-1, his team wasn't ranked -- and he also mentioned that it was the first time since the AP poll started in 1936 that a 5-1 Trojans team was unranked. The victory over the Irish will garner some attention; an upset of Stanford would garner even more.

Steve Megargee

Notre Dame hasn't lost its appetite for self-destruction. After committing 15 turnovers in its first four games of the season, Notre Dame didn't cough the ball up once in its next two games. But just when we thought the Irish had learned how to play mistake-free football, they regressed at the worst possible time. Notre Dame had rallied from a 17-0 deficit and was a yard away from tying USC late in the third quarter when backup QB Dayne Crist -- in the game after an injury to Tommy Rees -- fumbled a snap on third-and-goal. USC's Jawanza Starling picked up the loose ball behind the line of scrimmage and raced 80 yards for a touchdown. The Irish still had a shot to rally in the fourth quarter after cutting the lead to 24-17, but two more turnovers sealed their fate. After Cierre Wood fumbled a backward pass from Rees, USC recovered at Notre Dame's 18 to set up the game's final touchdown. Notre Dame's final hopes vanished when Nickell Robey picked off a Rees pass.

Michigan State can win with offense as well as defense. Michigan State headed into the weekend ranked second nationally in total defense, first in pass efficiency defense and third in run defense. But the Spartans showed Saturday that they also can win shootouts. They have a star receiver in B.J. Cunningham, an experienced quarterback in Kirk Cousins and a couple of quality running backs in Le'Veon Bell and Edwin Baker. Cousins threw for 290 yards and three touchdowns without an interception to outplay Heisman contender Russell Wilson in Michigan State's 37-31 victory over previously unbeaten Wisconsin. And after Wilson led two fourth-quarter touchdown drives as the Badgers erased a 14-point deficit against that highly regarded Spartans defense, Cousins responded by driving Michigan State beyond midfield, then hitting Keith Nichol on a Hail Mary as time expired. The final play certainly resulted from luck as much as execution, but the performance of Michigan State's offense the rest of the night was no fluke.